Measuring the Effect of Strengthened Concrete on the Fracture Characteristics of Notched Concrete Beams Through a Three-Point Beam Test

This study explores the effect of increased concrete strength on the behavior of concrete failure. Experimental testing using a three-point bend (TPB) test proposed by RILEM was carried out to calculate the value of fracture energy (G_F), stress intensity factor (K_IC), and characteristic length (lch) of the concrete. The values of G_F and l_ch, which are proportional to the fracture process zone based on the fictitious crack model, were employed to determine the effect of concrete strength on the concrete’s fracture characteristic. K_IC was engaged to describe the initial crack in the concrete. Four different concrete strengths of 40, 47, 53, and 100 MPa—were manufactured to produce notched beam specimens with single-sized notches 25 mm deep. Results revealed that the values of G_F and K_IC increased in the stronger concretes. However, the value of l_ch decreased significantly as concrete strength increased.

This study explores the effect of increased concrete strength on the behavior of concrete failure. Experimental testing using a three-point bend (TPB) test proposed by RILEM was carried out to calculate the value of fracture energy (G_F), stress intensity factor (K_IC), and characteristic length (lch) of the concrete. The values of G_F and l_ch, which are proportional to the fracture process zone based on the fictitious crack model, were employed to determine the effect of concrete strength on the concrete’s fracture characteristic. K_IC was engaged to describe the initial crack in the concrete. Four different concrete strengths of 40, 47, 53, and 100 MPa—were manufactured to produce notched beam specimens with single-sized notches 25 mm deep. Results revealed that the values of G_F and K_IC increased in the stronger concretes. However, the value of l_ch decreased significantly as concrete strength increased.